U.S. Pat. No. 5,078,110 discloses an arrangement for controlling an actuable element wherein the control unit generates an actuating signal when a jamming of the actuable element has been detected. The actuating signal leads to a shaking movement of the actuable element. In this way, an effort is made to loosen the jammed actuable element after the jamming condition is detected and maintain the availability of the motor vehicle equipped with the actuable element. The measures described in U.S. Pat. No. 5,078,110 are initiated after jamming is detected. In this way, there is only a short operating phase during which the availability of the motor vehicle is limited.
From published German patent application 3,327,376 it is known, in order to avoid jamming or tilting of an actuable element (throttle flap), to move the actuable element out of the rest position by allowing the engine to cool after the engine is switched off. Here, it is not considered that the jamming can be caused also by the collection of dirt at the end of the normal range of movement. The danger of jamming by such accumulations of dirt is not avoided by the procedure described in published German patent application 3,327,376.
Published German patent application 4,018,922 discloses that layers of dirt on potentiometer tracks can be removed in pregiven operating states such as during overrun operation. The actuable element connected to the potentiometer is moved in one direction out of the normal operating range and so pushes the contaminants out of the normal operating range. Although contamination is removed from the potentiometer tracks in this way, a jamming of the actuable element itself is only inadequately countered.